Toothbrush with removable head



M. w. v-ANNlcE TooTHBRUsH WITH REMOVABLE HEAD Dec. 23, 1952 Filed OGf..A ll. 1948 C .Mm MNM www www .www

Patented Dec. 23, 1952 UNITED STATES PATENT OFFICE 8 Claims.

|This invention relates to improvements in vbrushes and more particularly to improvements in brushes having replaceable brush means which are adapted to be removed from 'the brush when soiled, unsanitary or Worn to such an extent that they are no longer sufciently effective to perform the function for which they are designed.

My invention is exemplied in a toothbrush for the purpose of illustrating its manner of construction and mode of operation but it is obvious that the principles thereof may be embodied in a Wide variety of diiferent types of brushes adapted to perform a similarly wide variety of different functions.

It is a Well known fact that toothbrushes, the bristles of which normally remain in a damp condition because of being frequentlyimmersed in water, have a comparatively short effective life and it is frequently necessary to discard the entire brush even though the only portion of the brush which is worn are the tufts which perform the brushing function of the brush. In order to eliminate the wasteful discarding of the entire brush, toothbrushes having embodied therein replaceable brush elements would be desirable.

It is a primary object of my invention to provide a toothbrush or other brush which has a handle portion adapted to receive and hold a replaceable brush means in a novel way and which is so constituted that the necessity of mechanical latching means to retain the brush means in the handle portion is eliminated.

Another object of my invention is the provision of a brush having a replaceable brush means which is adapted to be inserted in the handle or base of the brush with a modicum of y difficulty and which is also adapted to be removed therefrom with relative ease. l

The utilization of mechanical latching means for retaining and locking the replaceable brush means in toothbrushes frequently results in the shifting of the brush means-while in use or its falling from the receptacle or member in which it is secured in the handle of the tooth-brush. When such dislodgement of the replaceable brush means or the latching means occurs while the toothbrush is in use, it frequently results in damage to the gums or mouth tissues of the user.

A further object of my invention is the provision of a toothbrush having replaceable brush means which, while it is adapted to be easily installed in the handle of the brush and as relatively easily removed therefrom, nevertheless is securely positioned in the handle so no shifting fof the replaceable brush means or no danger of Vits'falling from the handle may occur.

An additional object of my invention is the provision of a brush having a replaceable brush means which is adapted to be secured within a recess or receptacle in the brush handle by means of the dynamic and frictional action of the tufts embodied in the brush means.

Another object of my invention is the provision of a brush having a replaceable brush `means which includes a central bar member adapted to be inserted in a central recess provided in the handle and which mounts a plurality of tufts which are themselves adapted to retain the brush means in the recess without the utilization of any other mechanical expedients to hold the brush means within the handle.

A further object of my invention is the provision of a brush with a handle providing a recess adapted to receive a replaceable brush means, said recess being provided with Walls designed to seize upon the tuft means embodied in the brush means of the toothbrush to compress or deform the tuft means and cause them to be frictionally and dynamically locked against the walls of the recess to hold the brush means securely but removably therein.

It is desirable that each member of a family group have allotted to him a toothbrush having a handle of distinctive color in order to prevent the inadvertent use of the toothbrush of one person by another. The provision of a toothbrush having replaceable brush units permits each memberl of a family group to retain the handle of a toothbrush having a distinctive color for an indefinite period and prevents the confusion that results when one member of a group purchases a toothbrush similar in color to the toothbrush of another member.

When conventional toothbrushes are in use for a certain period of time the bristles thereof tend to splay and diverge from the vertical or parallel attitude in which they were arranged When the toothbrush was first used. This splaying action is due, in large part, tol the fact that considerable sideward pressure is brought to bear upon the bristles when they are in a moist condition and they thus tend to set in a spread attitude after the brush has been in use for a moderate period of time.

It is an additional object of my invention to provide a toothbrush having a replaceable brush means and incorporating a plurality of tufts Vmounted in a mounting bar, said tufts being adapted to be so oriented when the brush means is inserted in the handle of the toothbrush, that the tufts at their upper portions are inwardly inclined to counteract the splaying effecten- 3 countered when the brush is placed in use. Another object is to provide a brush in which the tufts in their initial position converge toward each other, irrespective of hcw such tufts are secured in place.

An additional object of my invention is the provision, as an article of manufacture, of a brush unit in which the tufts provide intermediate portions molded or otherwise iXedly secured in a mounting bar. the possibility of the bristles pulling out of the mounting bar is eliminated and the effective life of the brush prolonged.

A further object of my invention is the provision of a toothbrush having replaceable brush means which can be readily removed from the. recess in which it is retained to permit deposits of a dentifrice or other accumulated ,foreign matter to be flushed from the base of the tufts and the recess itself, thus insuring a more sani tary tooth brush.

Other objects and advantages of my invention will become apparent from a consultation of the following specification and the accompanying drawing, which is for the purpose of illustration only, and in which:

Fig. 1 is a vertical elevational View of a toothbrush constructed in accordance with my invention;

Fig. 2 is a partly sectional, partly plan view taken along the broken line 2 2 of Fig. 1;

Y Fig. 3 is a vertical, partly section, partly elevational, enlarged view taken on the broken line 3--3 of Fig. 1;

Fig. 4 is an enlarged perspective showing the brush means in its expanded stage;

Fig. 5 is a perspective view of the brush means in a sanitary package prior to insertion in the handle of the toothbrush; and

Fig. 6 is a top plan view-showing the manner in which the top portions of the tufts spread out to increase the surface coverage of the tufts.

Referring to the drawing, show a toothbrush I which includes an elongated handle portion II having integrally formed at one end thereof i abase or head portion I3. ln the present embodiment of my' invention the handle portion Il and the head portion I3 are formed of a translucent colored plastic but it is conceivable that any other desirable material may be utilized.

The head portion AI3 of the brush ill is provided with an elongated, central recess I5 which maybe molded within the head portion i3 simultaneously with the molding thereof or which may be subsequently formed therein as by drilling or by use of any other suitable process. The elongated central recess I5 is defined by side walls I6 and end wallsil, the end wallsl Il being formed on an arc, and a bottom wall I8 serving to unite the side walls. I6 and the end walls il.

'Y Although the recess I5 has been described as being of an elongated nature, it is conceivable that a recess having a, different configuration may be utilized and it is not intended that be limited to the specific configuration of the recess as shown.

The side walls Ia which define the elongated central recess l5 preferably comprise 'a plurality y of longitudinally spaced grooves or concavities 2G, said concavitieshaving outer walls 2l which are inwardly and upwardly inclined, for a purpose lwhich will be described in greater detail below. The remaining portions of the side walls I6 may be similarly inclined or undercut or may By so mounting the tufts d be parallel. ln either event the side walls I6 and Lne end walls li extend to the upper face of the l ad portion i3 and denne a restricted-width opening on the recess i5.

central recess i5 is adapted to serve as a `eceptacle for a brush unit or brush means 24 which is designed to be removably inserted therein. The brush means 2a includes a toit-retaining element shown as an elongated bar 25 which has nxedly secured and preferably molded therein a plurality of tufts 2l The tufts 2 are secured in the lower portion of the elongated mounting bar 25 and are spaced longitudinally therealong, extending from Vopposite sides thereof. The thickness of the bar is preferably slightly less than the distance between the side walls I and the length of the bar is preferably slightly less than the distance between the end. walls Il so that the bar itself does not bind in the recess when placed therein.

When the brush means 2d is in its expanded state, the tufts 2l lie with their longitudinal axes normal to the longitudinal plane yof the mounting bar As best shown in Figs. 3 and 4l of the drawing, the tufts 2? are molded or secured in the lower portion of the elongated mounting bar 2d at their intermediate portions 29 and thus two tufts which` are oppositely disposed are formed from the saine bristles. The tufts 27 are preferably composed of a plurality Vof bristles which are made of nylon, a synthetic polymeric amide, or other thermo-plastic materials currently used as bristles in brushes.

`Shown in Fig. 5V of the drawing is a contemplated.V holder 33 which is adapted to hold'the tufted bristles in substantially U-shape and to keep the brush means 25% in a sanitary condition until it is inserted in the head portion I3 of the tooth brush le. rlhe holder 33 includes a' transparent or translucent wrapper holder 34, which may be formed as a band of sui-table plastic material or which may be a plastic sealing tape adhered to itself about the brush means 2153. The holder 33, in addition to preserving the brush ymeans Eil in a sanitary condition until it is used, servesrto hold the brush means and the tufts 2l in a position in which theyniay more easily and readily be grasped to insert the brush means 24 in the receptacle le provided in head .portion I3 of -t ie toothbrush Ie. After insertion of the brush means 2d in the receptacle I5, the holder is stripped yor otherwise removed from the brush means if the holder has not previously been renewed or has not been released during the insertion of the brush means. y

To insert the brushmeans 2e, the tuftmounting bar 25 is aligned with the elongated central recess I5 and a downward pressure is brought to bear upon the tufts 21, the holder 33 orthe tuftinounting bar 25 to force this bar downwardly into the recess I5 through the restricted-width passage. Automatically, the inner or lower portions 3@ of the tufts 27 are brought into registry with and inserted inY the substantially4 vhernispherical concavities 2@ which .are provided in the sidewalls I5 of the recess I5., Asbest shown in Fig. 3 of the drawing, the downwardmovement of the lower .portions 3l)Y of Ythe tufts 2'! causes the tuftsfto be bent upwardly or .inwardly byengagementwith theinclined walls 2l of the cencavities 2li and this is true whetheror not the holder 33 was removed prior to the insertionof 4 the brush unit or whether or not such a holder tom I8 lof the elongated recess I5, the main portions of the wtufts 21 will have been bent beyond a parallel relationship and into convergingrelationship, following the convergence of the outer walls 2| of the grooves or concavities 20. Since the tufts 21' are formed of a plastic material having resilient properties, the tufts 21 tend constantly to expand against the sloping walls 2| of the concavities 20 and exert -a considerable frictional effect upon these sloping walls tending to resist the dislodgement of the brush means 2A from the central recess I5.

In addition, the frictional effect is increased due to the undercut or sloping relationship of the walls 2| of the opposed grooves or concavities 2|). Also, the restricted-width passage, through which the brush means must be forced to enter the recess I5, acts as a detent means to retain the brush means in the recess once it has been forced therein. Any withdrawal of the brush means would necessitater a further bending of some of the bristles to pass through the restricted-width passage and this is resisted by the resilience of these bristles.

Finally, the tufts are held in their converging relationship by a reaction force exerted thereon by the sloping walls 2|, this reaction force being perpendicular to the walls 2| and thus having a component exerting a `downward force on the tufts tending to force them further into the recess I5. This is quite aside from frictional force and would be present even if the engagement between the bristles and the walls 2| were frictionless. Such downward component tends to establish a definite force holding the bottom s-urface of the bar 25 in pressural contact with the bottom wall I8 of the recess I5. lCorrespo-ndingly, the resilience of the tufts 21 and the nip-ward convergencel of the walls 2| provide a dynamic holding action retaining the tufts in place in the concavities 2t. Y

As may be best seen from Fig. 2 of the drawing, the tuft-mounting bar 25 can thus be maintained within the central recess I in a spaced relationship to the end walls I1 and the side Walls l, the sole means of'holding the brush means 24 Within the central recess I5 and the concavities-2i) being the resilient tufts 21.

In addition to providing a means for holding the brush means 24 Within the head portion I3 of the toothbrush I0 the inclined walls 2| of the concavities 2|! serve to incline the upper portions 3I of opposed tufts 21 toward each other so that these upper portions 3| converge toward their tips. As best shown in Fig. 3 of the drawing, the upper portions 3| of the tufts 21 can be brought into relatively close contiguity and the tufts tend to resist the splaying action which is induced by the sideward pressure usually applied to the tufts during rocking or turning of the Y brush to sweep the tufts away from the gums and toward the ends of the teeth. Of course, the continued use of the toothbrush will eventually cause the tufts 21 to splay to some extent but when they do they will assume a substantially parallel relationship which will still permit the brush to be utilized for a much greater time than is possible withconventional brushes in which the tufts are initially in such parallel relationship.

As best shown in Fig. 6 of the drawing, when the brush means 24 is inserted in the head portion I3 of the toothbrush IG the top portions 3| of the tufts 21, in addition to being caused to diverge from their vertical axes into close lateral con- 1 6 tiguity to each other, are caused to spread out longitudinally of the brush so that the ends of the tufts assume an elliptical lshape which permits them to give a more effective area coverage when the toothbrush is in use.

The longitudinal spreading of the top portions 3| of the tufts 21 may be attributed to the compressive effect of the inclined side walls 2| of the concavities 20 upon the outsides of the lower portions 30 of the tufts 21. If desired, the longitudinal spreading of the top portions'SI ofthe tufts 21 may be accentuated by increasing the width of the tuft-mounting bar 25 sufficiently toV cause the insides of the lower portions 30 of the tufts 21 to'contact and be compressed by the bar. Usually, however, this is neithernecessary nor desirable.

If the bristles forming the tufts 21 are initially of the same length when the brush means is in its forward position,'shown in Fig. fl, bending of the tufts into the configuration of Fig. 3 will cause the tips of the bristles Ato lie in an arcuate path` to present an arcuate brushing surface. This is often advantageous but if desired the tips of the tufts can be initially cut at an angle so that when the tufts are deformed into the configuration of Fig. 3 the tips of the tufts will lie substantially in a single plane parallel to the top face of the head portion I3.Y n

Of course, there is a wide variety of methods by which the tufts 21 may be fixed or moldedin the tuft-mounting bar 25 of the brush means 24. The preferred method is to mold the tuftforming bristles in place when the bary 25 is molded so that the material of the bar is molded around the tufts. The bar is preferably formed of a thermo-plastic or thermo-setting plastic material. v

Althoughv I have shown and described aA specilic embodiment of my invention for the purpose of illustrating the manner of construction and the mode of operation thereof, it it conceivable that changes and substitutions may be made in the details shown and it is not intended that the invention be limited thereto. I desire, therefore, to be afforded the full scope of the following claims.

I claim as my invention: e

1. In a brush, the combination of: La handle comprising a base providing side and end Walls defining an elongated recess; and a replaceable brush unit separate from said base and removably received by said recess, said brush unit comprising an elongated rigid bar and a plurality of tufts xedly embedded in spaced relationship therein and extending from opposite sides thereof, the length of said bar being less than the distance between said end walls and the Width of said bar being less than the distance between said side walls, said brush unit being insertable in said elongated recess and said tufts being bent by such insertion to extend away from said base, the bent tufts lying in frictional contact with said side walls and providing substantially the sole means for retaining said bar in said elongated recess.

2. A combination as defined in claim 1, in which said elongated recess opens on a face of said base, and in which the opposed side walls provide tuft-engaging portions converging toward each other in a direction toward said face whereby the opposed tufts extending from opposite sides of said elongated bar provide portions beyond said face which converge toward each other toward the ends of said tufts.

` l3. A combination as fdened in claim 2 in which 'saidf-tu-ft-'engagingportions "effi-said side fwalls' emprise eenvergingfconeavities -facing each ot-lierfon-foppositeefsides offsaidv elongated' recess `*a-nd'spafceda vdi's'tan'ee corresponding to V"the spacing of said tufts retained'by 'said"bar,' the'o'pposed "concavities providing bottom walls con- -verging fin" said direction "toward lsaid face.

` 4. A -brush fas de'ned-inv claim 1 in which "sa'ic'l'base` providesa face' onwliichsaid elongated recess -{opensfa'nd in which saidfelongatedv rigid fba'riarovidesnpper yedgesiibs't'antially l'ush 'With said face of saidv base. f

5.1 A' brush las definedV in'claiin 1f in which said 'basefprovidesI a -faee'on which said-elongatedirecessOpensjsaid elongated'recess providingra bot- "tirwalland in which said elongated rigidfbar provides an upper edge substantially ,fluslorv with saidv -faeeoiesaid lbasev and a vlower edgel in contact {wi-th said bottom "wan vwhen 'said brush unit; isl in' said Yelongated recess.

"BH'I'n-a brush, thecinbinationof: va handle ornpris'ing'a baseliaving'side and end walls Ide- 'ning 4an elongated'pree'ess openingen a faceV of said base; an elongated frigid bar' removably retainedin said-elongated recess, said fbar being ofv a widthmaterially less than' the distance "between said side walls and of a length 'less than the Vdistancev betweensaid end Walls, s'aid Ybar being insertable infsaidelon'gated recess; `and Vmeans for holdingfsaid bar insaid recess, said -holding 'Y means iclding a plurality of tufts 'fniedly secured inV said bar and extending from vopposite sides tnereoftofengage and'be bent by said Side Walls during insertion of *said bar in saidelongated recess, the engagement between the bent tufts andsaid side walls applying sub- V`'stantiallythe solev restraining force for retaining said bar in said elongated recess. n

7. 'In a brush thecombination of: a base providing a faeeand an elongatedrecessl opening on lsaid facefsaid elongated recess being boundedby sidewallsy and by end walls;A wallsdefining a plurality of longi'tudinal-ly-spacedr ltuft--reizzeiving -`goovesfonf eachside -wall yand opening atop- *posed-positions on said elongated recess, each pair of grooves forming a`tuft-receiv`in'g space Wider than the distance between said side walls, said opposed grooves providing bottom walls converging in a direction toward said face;'4 a tuftretaining bar of a length less than the distance between said end walls and of a width less than v fthe distance between'said'side wallsto niove freely into V"said elongatedrecess;` andfafplurali'ty'f positions correspondingto the longitudinal lspacming of Ysaid tuft-r'eceiving spaces, said tu'fts'profreely insertable in said recess and a 'pluralityof tufts ofi plastic bristles 4vextending througlfiV and molded at their intermediate portions in`sad tuft-mounting element, said bristles rproviding ends extending sidewardly from opposite si'desof said tuft-mounting element to form opposed tufts, insertion of said brush unit in said recess bending such opposed tufts by contact withsaid side Walls.

MARVN W. VANNCE.

- REFERENCES CITED i The following vreferences are of record in the lc of this patent:

UNITED STATES PATENTS Number Name Date 824,087 Babcock June 26," 1906 1,497,495 Fincke June 10, 1924 1,769,747 Major July 1, 1930 2,225,331 Campbell Dec. 17, 1940 N.2,253,210 Psiharis Aug; 19, 1941 2,558,332 Artale June 26,l 1951 FOREIGN PATENTS Number Country k Date 123,472 Great Britain Feb. `27, 1919 253,951 Great Britain ;Nov;18, 1926 500,937 Germany June l26, 1930 

